ACL injury

Let's talk today about ACL injuries.

Do you remember that old children's song that goes, "The knee bone's connected to the thigh bone," and so on? Well the thigh bone's connected to the shin bone, and one of the four ligaments that connects these two bones is called the anterior cruciate ligament or ACL. The ACL sits in the middle of the knee. It's main job is to prevent the shin bone from sliding in front of the thigh bone.

So, how do most ACL injuries occur?
Well, getting tackled in football is just one way to hurt your ACL. You could also over extend your knee joint while playing other sports, like basketball or soccer, or while skiing. Or, you could injure your ACL if you quickly change direction while running, or land the wrong way from a jump.

Some ACL tears are just partial, while others are complete. The injury that has damaged your ACL can also tear other ligaments or cartilage in your knee.

So, what should you do if you think that you might have a torn ACL?
Well, if you've injured your knee and it swells up, hurts, or makes a "popping sound," or gives way while you walk, you could have an ACL injury. So, stop whatever that you're doing; even if you're just about to score the game-winning touchdown. Try not to move your knee. See your doctor as soon as you can because you may need an MRI or x-ray so your doctor can see exactly what type of injury that you have.

You can treat an ACL injury with ice, rest, and pain relievers such as ibuprofen or acetaminophen. But you may also need physical therapy to get your knee moving normally again. If the tear is so bad that you can barely walk on your leg, your doctor may recommend surgery to rebuild your torn ACL.

Whenever you run, jump, or play sports, take it easy on your knees. Talk to your doctor or a physical therapist about ways to prevent knee injuries during play. And if you ever hurt your knee so badly that your foot turns blue and feels cool to the touch, get medical help immediately because that's a sign that you've dislocated your knee joint, and you may have injured the blood vessels to your foot.

Version Info

  • Last reviewed on 11/16/2011
  • Mitchell W. Hecht, MD FACP, Internal Medicine private practice in Roswell, GA; author of the nationally-syndicated medical column 'Ask Dr. H.' Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M. Health Solutions, Ebix, Inc.

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